"Conservation Groups Challenge EPA's Acid Rain Standards"

"The petition for review was filed in the federal Court of Appeals for the District of Columbia Circuit by the Clean Air Council, Center for Biological Diversity and National Parks Conservation Association, represented by the nonprofit law firm Earthjustice.

Today's action has a long history.

The Clean Air Act requires the EPA to set so-called "secondary" air quality standards limiting ambient concentrations of air pollutants that affect "public welfare," which includes ecosystems and natural resources.

The Center for Biological Diversity and other groups sued the agency in 2005 over its failure to review the secondary standard for sulfur and nitrogen compounds that react with the water molecules in the atmosphere to produce acid rain. The standard was first established in 1971 and has not been updated. "